• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.64.2-64.2
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• 2010

The objective of this study is to make a comparative study of the operation performance of different type of solar collectors. A flat-plate collector, a single-glazed evacuated collector and a double-glazed evacuated collector are used in this study. These 3 type of collectors are connected in series in the order of a flat-plate collector, a single-glazed evacuated collector and a double-glazed evacuated collector. This experimental facility is a kind of a solar system with a controller, a heat exchanger, a storage tank and a circulation pump. Each collector has a different collection area(flat-plate collector-$6.00m^2$ total area/$5.61m^2$ aperture area, double-glazed evacuated collector-$6.04m^2$ total area/$4.92m^2$ aperture area, single-glazed evacuated collector-$7.65m^2$ total area/$5.61m^2$ aperture area) and its performance characteristic respectively. The experiments have been demonstrated at around $70^{\circ}C$ operating temperature(flat-plate collector inlet temperature). The thermal collecting efficiencies of each collector are obtained under the different insolation and operation condition as a result.

• Journal of the Korea Concrete Institute
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• v.20 no.1
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• pp.35-41
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• 2008

In general, flat plate systems have been used as a gravity load resisting system (GLRS) in building. Thus, this system should be constructed with lateral force resisting system (LFRS) such as shear walls and brace frames. GLRS should retain the ability to undergo the lateral drift associated with the LFRS without loss of gravity load carrying capacity. And flat plate system can be designed LFRS as ordinary moment frame with the special details. Thus, flat plate system designed as GLRS or LFRS should be considered internal forces (e.g., unbalanced moments) and lateral deformation generated in vicinity of slab joints render the system more susceptible to punching shear. ACI 318 (2005) allows the direct design method, equivalent frame method under gravity loads and allows the finite-element models, effective beam width models, and equivalent frame models under lateral loads. These analysis methods can produce widely different result, and each has advantage and disadvantages. Thus, it is sometimes difficult for a designer to select an appropriate analysis method and interpret the results for design purposes. This study is to help designer selecting analysis method for flat plate system and to verify practicality of the modified equivalent frame method under lateral loads. This study compared internal force and drift obtained from frame methods with those obtained from finite element method under gravity and lateral loads. For this purposes, 7 story building is considered. Also, the accuracy of these models is verified by comparing analysis results using frame methods with published experimental results of NRC slab.

• Journal of the Korea Concrete Institute
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• v.14 no.6
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• pp.949-960
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• 2002

Flat plate structures under lateral load are susceptible to punching shear failure of the slab-column connection. To prevent such brittle failure, strength and ductility of the connection should be ensured. However, due to complexity in the behavior and difficulty in simulating the actual load and boundary conditions of the flat plate system, it is not easy to obtain reliable data regarding to the strength and ductility from the previous experimental studies. In the present study, a numerical study was performed for interior connections of continuous flat plate. For the purpose, a computer program for nonlinear FE analyses was developed, and the validity was verified by comparisons with the existing experimental results. Through the parametric studies, the variations of bending moment, shear, and torsional moment around the connection were investigated. Based on the findings of the numerical studies, the aspects which need to be improved in current design methods were discussed. The results of the present study will be used for developing a design method for the flat plate-column connection in the companion paper.

• Journal of Korean Society of Steel Construction
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• v.17 no.4 s.77
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• pp.481-490
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• 2005

This paper summarizes the full-scale test results on the CFT column-to-flat plate connections subjected to gravity loading. CFT construction has gained wide acceptance in a relatively short time in domestic building construction practice due to its various structural and construction advantages. Constructing an underground parking floor as a flat plate system is often regarded as essential for both cost savings and rapid construction. Efficient details for CFT-column-to-flat-plate connections have not been proposed yet, however, and their development is urgently needed. Based on some strategies that maximize economical field construction, several connecting schemes were proposed and tested based on a full-scale model. The test results showed that the proposed connection details can exhibit punching shear strength and connection stiffness comparable to or greater than those of their R/C flat plate counterpart.

• Journal of the Korean Society for Advanced Composite Structures
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• v.5 no.2
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• pp.9-14
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• 2014

Main topics in this study is a new structural detail for connection between H-Steel or SRC column and flat plate slab. We carried out to evaluate the punching shear performance of H-steel or SRC column + RC slab system for vertical load and lateral load. From the test results structural characteristics - yield moment, yield rotation, maximum moment, deformation capabilities ect. - are obtained and evaluated. In this paper as a shear reinforcement for supporting region of plate closed stirrup type and shear band are used, and their test results are compared.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.7
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• pp.833-841
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• 2007

The aim of this paper is to analyze the conjugate problems of heat conduction in solid walls coupled with laminar free convection flow adjacent to a vertical flat plate under boundary layer approximation. Using the similarity transformations the governing boundary layer equations for momentum and energy are reduced to a system of partial differential equations and then solved numerically using Finite Difference Method(FDM) known as the Keller-box scheme. Computed solutions to the governing equations are obtained for a wide range of non-dimensional parameters that are present in this problem, namely the coupling parameter P. the Prandtl number Pr and the heat generation parameter Q. The variations of the local heat transfer rate as well as the interface temperature and the friction along the plate and typical velocity and temperature profiles in the boundary layer are shown graphically. Numerical solutions have been consider for the Prandtl number Pr=0.70

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.1 no.2
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• pp.182-189
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• 1989

The propose of this study is augmentation of heat transfer without additional external power in 2-dimensional impinging air jet. The passive heat transfer augmentation method tried in this experimental study is placement of rod bundles with the clearance, 2mm, in front of the heat transfer surface. The effects of pitch distance among rods and nozzle-to-target plate distance are investigated. The overall heat transfer rate of flat plate with rods reaches maximum at H/B=10 and P=40mm, and for H/B=2 and P=40mm the augmentation rate of heat transfer becomes maximum to a value which is about 1.57 times that of the flat plate without rods.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.225-228
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• 2002

Supersonic jet impingement on a flat plate has been investigated to show the flow physics for different jet heights and to demonstrate the adequacy of the characteristics-based flux-difference Wavier-Stokes code Current study also compares the steady-state solutions obtained with variable CFL number for different grid spacing with the time-accurate unsteady solutions using the inner iterations, displaying a good agreement between the two sets of numerical solutions. The unsteady nature of wall fluctuations due to bouncing of the plate shock is also uncovered for high pressure ratios. The methodology is then applied to a complex vertical launcher system where the jet plume hits the bottom wail, deflects into the plenum and eventually exits through the vertical uptake. Flow structures within vertical launcher system are captured and solutions are partially verified against the flight test data. Present jet impingement study thus shows the usefulness of CFD in designing a complex structure and predicting flow behavior within such a system.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.600-603
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• 2003

The floor thickness in residential buildings may not satisfy the floor vibration criteria even though the thickness is determined by the serviceability requirements in current design provisons. Thus it is necessary to develop the procedure to determine slab thickness that satisfies the floor vibration criteria. In this study provide the methods to determine the slab thickness that satisfies the vertical floor vibration criteria for several sizes of flat plate floor system. Randomness inherent in young modulus of concrete and heel drop intensity was accounted. For this purpose Monte Carlo simulation procedure was adopted.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.871-874
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• 2008

In the beginning of KBC-2005, many structural engineers had have difficulty in designing the flat plate structures. Recently KBC-2005 has been revising. At this point, we need to study the lateral resisting systems which are based on KBC-2008 draft and applicable to the flat plate structure. When the RC structure system of KBC 2008 draft is compared with that of KBC-2005, there are some differences. (1) Structural system and height limitations according to seismic design category (2) Special Requirement such as special RC shear wall (3) New lateral force resisting system such as shear wall-frame interaction system The KBC-2008 will give structural engineers to choose the various lateral force resisting system